The disclosure relates to a microfluidic device, to a method for producing a microfluidic device and to the use of a microfluidic device.
Microfluidic devices are employed, for example, as lab-on-a-chip systems within the framework of molecular-diagnostic laboratory applications. The use of microfluidic devices of this type not only makes a diagnosis possible in a large laboratory or a medical practice, but also, for example, a patient can himself or herself carry out at home appropriate checks, for example of markers or of the blood sugar level, with the aid of the microfluidic device.
Microfluidic devices of this type are produced, for example, from polymer plates with integrated ducts and/or cavities in order to transport and/or filter liquids and the like. So that the microfluidic device can be acted upon with liquids or compressed air, it can be connected to a fluid-providing device via hoses. Via the hoses, the fluid-providing device can act with pressure in a directed manner upon the ducts and/or the cavities and consequently move liquids. Furthermore, pneumatic control of microfluidic pumps and/or valves is also possible. So that individual functions of the microfluidic device can be performed in a directed manner, different pressures or pressure levels are required. These are generated outside the microfluidic device by a pneumatic device and are provided to the microfluidic device via additional connections.
A microfluidic stop valve for a microfluidic device became known from WO 2007109375 A2. The microfluidic stop valve in this case comprises an inlet, at least three diaphragm valves comprising valve inlets, valve outlets, valve controls and elastomeric diaphragms. When a valve control is acted upon with pressure or a vacuum, the elastomeric diaphragm is deflected in order to modulate a flow of a liquid. Two of the valves are connected to a third valve in such a way that a sufficiently high vacuum at an inlet of the microfluidic stop valve causes the third valve to be opened and sufficient pressure at the inlet of the microfluidic stop valve to be provided so that the third valve is closed.
US 200770166199 A1 has disclosed a microfluidic system, comprising a pneumatic multiple distributor with orifices and a chip distributor with ducts, in order to send pneumatic signals from the corresponding orifices to pressure-actuable diaphragms in a microfluidic chip. The ducts in this case transport the pneumatic signals according to a fixed configuration of the pressure-actuable diaphragms in the microfluidic chip. The microfluidic chip likewise comprises reagent reservoirs in order to store fluidic reagents and outlet stores for storage of reaction products of the fluidic reagents.